Paper knife



K'uNlo Ml'ro April 14, 1959 PAPER KNIFE Fi1edoGt.28, 1957 1 Mx BY fw/zii ATTORNEYS United States Patent O PAPER KNIFE Kunio Mito, Utsunomya, Japan Application October 28, 1957, Serial No. 692,850

1 Claim. (Cl. 30-280) This invention relates to a paper knife and is more particularly directed to a paper knife suitable for use in unsealing paper-bags such as envelopes, sealed containers of drinks, and others.

According to this invention, there is provided a paper knife comprising a holder having a pair of projecting arms which are spaced from each other by a long and narrow slit, and a blade iixedly attached to the top portion of said arms so that it is laid across the slit and its keen edge is directed inwards.

It is an object of this invention to provide a novel paper knife which may be conveniently used as a substitute for ordinary scissors and the like to cut off a corner of a paper-bag such as an envelope or the like for unsealing the same. Another object of the invention is to provide an improved paper knife which is simple in construction, easy to handle, small in volume and weight and economical to manufacture. Further, another object is to provide a paper knife which can be carried or used in safety so that the same is suitable especially for travellers or picknickers or other persons for unsealing a papermade container of such drinks as milk, fruit juice or others at a station or any other place where they will have much trouble to get scissors and the like.

Further and other objects and features of the invention will be made clear from the following description of the embodiments shown on the accompanying drawings, in which:

Fig. 1 is a perspective view of a knife embodying the invention,

Fig. 2 is a sectional View taken along the line A-A in Fig. l,

Fig. 3 is a sectional View taken along the line B-B in Fig. 1,

Fig. 4 is a perspective view of the knife which is in use,

Fig. 5 is a perspective view showing another embodiment of the invention, and

Fig. 6 is a perspective view showing further another embodiment of the invention.

Referring now more particularly to the accompanying drawings, in which like and corresponding parts are designated by similar reference characters. Numeral 1 is a holder having a pair of projecting arms 2 and 2 which are almost parallel and are spaced by a long and narrow slit 3, and numeral 4 is a thin blade, such as that of a safety-razor, which is xedly attached to the top portion of said arms 2 and 2 so that it is laid across the slit 3 and its keen edge 5 is directed inwards. The holder 1 and the arms 2 and 2 may be made in one body out of a twofold strip of such a material as paper, metal, synthetic resin or the like as is shown in Figs. l to 4 inclusive, or out `of a two-ply or single-layer strip of the similar material as is shown in Fig. 5, or out of a wire properly curved as is shown in Fig. 6. In the embodiment shown in Figs. l to 4 inclusive, a thin metal strip which is provided at the middle portion thereof with a long and narrow opening is so folded in two that the fold edge thereof -forms the top ends of the arms 2 and 2, and the thin blade 4, of which the keen edge 5 is directed inwards, is placed in the fold so that it is rmly held between the two superposed layers and is prevented from being pushed away forwards by the fold edge thereof. The blade 4 is also prevented from being moved sideways by a pair of side fingers 6 each formed from a side edge of one of said two layers with the finger 6 extending laterally thereof and bent upwardly towards the other of said two layers as shown in Figs. 1 and 3 of the drawings. The two layers of the strip are combined with each other by a pair of lugs 7 and 7 which project integrally from one of the layers and are bent inwards on to the outside surface of the other layer. lIn the embodiment shown in Fig. 5, the two superposed layers are secured by binding agents and the both ends of the blade 4 are held between the two layers at the top portion of the arms 2 and 2. The blade 4 may be ixedly attached to the arms 2 by any desired means such as solders, binding agents, screw-pins, rivets or others.

The knife shown in Fig. 6 comprises a U-shaped wire 1 having legs 2 connected by a blade 4 joined to said legs which blade has a cutting edge 5 directed towards the base or handle of wire 1.

Referring to Fig. 4, numeral 8 is a tetrahedral form of paper-bag which is usually formed out of a short papermade cylinder by sealing the top and bottom ends thereof so that the sealed edges are at right angles with each other. A paper-bag of this type is recently used as a sealed container of milk or fruit juice :or other drinks to be sold at a station or any other place, and the knife of this invention is especially suitable for use in unsealing such containers. If a corner of the bag 8 is inserted through the slit 3 between the arms 2 and 2 of the holder 1 `of Figs. 1, 5 or 6 held by a person and then the holder 1 is pulled to move towards the person, the keen edge 5 of the blade 4 will cut oif the inserted corner of the bag 8, whereby the bag 8 is provided with an opening at the corner thereof and -the drink contained therein is prepared to be drunk through that opening. During this operation, the arms 2 and 2 move along the 'both side surfaces of the inserted corner of the bag 8 and hold the corner from both sides thereof, whereby the cutting action of the blade 4 can be secured. Paper-bags of other forms can be unsealed in almost the same manner as described above.

What I claim is:

A paper knife comprising a holder having a handle portion and a pair of projecting arms spaced from each other by a long and narrow recess, and a blade fXedly attached to the free end portions of said arms across said recess and with its cutting edge directed inwards of said recess towards said handle portion, said holder being formed of a thin metal strip having a long and narrow opening in its central portion and folded in two with the fold edge thereof forming the top free ends of said arms and the other end portion forming said handle portion, said -blade being held at its sides in between the fold edge of said strip so that it is prevented from being moved outwards by said fold edge, a pair of side members which are integral with and project outwards from the side edges of one of the two layers of said strip and are bent inwards almost vertically towards the other layer for retaining said blade from being moved sideways.

References Cited in the file of this patent UNITED STATES PATENTS 757,551 Guest Apr. 19, 1904 1,020,753 Ford Mar. 19, 1912 2,082,982 Schumacher June 8, 1937 FOREIGN PATENTS 162,945 Switzerland Sept. 16, 1933 

